Attachment for reversible dobby heads



Dec. 30, 1930. w. M. WATTlE I ATTACHMENT FOR REVERSIBLE DOBBY HEADS Filed July 22, 1929 7 Patented: Dec. "30, 11 930 WILLIAM, mawA TIE, or WORCESTER,= MAssAc ius s,- ns'sreivoiaiitro CnoMrToNa,

SACHUSETTS I l ATTACHMENT FOB, EEvEEsIBLE Toners DS I Application filed July 22, 1. 529. -Seria1l\l'o.'380,];12.

This invention relates to a reversible dobby head of the type in which the vibrator lever-shave three. separate positions; high, low and intermediate. Such a dobby is shown in the prior patent to Hussey and Stebbins, No. 1,691,156, issued November 13, 1928.

In such reversible heads, it is necessary that the vibrator levers be maintained in intermediate position at all times except when they are about to be raised or lowered. It frequently happens thata dobby will contain extra vibrator levers in excess of the number of harnesses in use for a particular fabric. Inorder to maintain such extra levers in intermediate or neutral position, it has been necessary to provide intermediate pattern links for each such extra vibrator lever throughout the length of thepattern chain.

It is the object of my invention to provide a simple attachment by which an extra vibrator lever may be maintained in intermediate position without the necessity of providing pattern chain links therefor.

In the preferred form, my invention consists in the provision of a series of removable supporting members which may be conveniently inserted in the dobby whenever extra levers are to be .rendered inoperative.

My-invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

A preferred form of the invention is shown in the drawings in which Fig. 1 is a side elevation of a reversible dobby head;

Fig. 2 is an enlarged side elevation of certain parts; and

4'0 Fig. 3 is'a detail sectional view, taken substantially along the line 33 in Fig. 1.

Referring to the drawings, Ihave shown a portion of a loom frame 10 on which a dobby frame 12 is mounted. A plurality of vibrator levers 14am pivoted at 15 in the ram an S rp n e aar W i k.

are pivotedat 17 onsaid levers:

LinkslSare pivoted at19. to the/vibrat on.

gears -16:and are also pivotally connected to the :harness levers or ja'cks20, Each vibrator, gear 16 is providedwitha segmental slot22,

intowhich extends a lugor projection 24 on the vibratorlever. This projection 24 alter-f I nately engages the opposite ends ofthe' segmental s'lot 22 and thus limits angular move mentthereofto substantially a halfrevolur' tion. Driving or cylinder gears" 24 and 26 are mounted in the frame 12 and are continuously rotated by suitable driving mechanism, not shown. w

T, Each vibrator lever, is provided with a roll SOfengagingthelinke -of a pattern chain 32;;

The 'chain 32 is provided with high,low and: intermediate links by which; the vibrator levers are positioned to engage thenpper or the, lower cylinder gears or are held inintermediate or neutral position. p It will be obvious that-,the vibrator gears can make only a: half revolution in agiven.

direction and that any further movement thereof mustbe a'half revolution in theopposi-te direction. If thevibratorgear is leftv in its raised position duringtwogsuccessiye revolutions of the upper cylinder gear 24, it

will be obvious that .the cylinder. gea'r wi'li engage the teeth of the vibrator gear on, its

second revolution, but willbe unable to rotate the gear furtherin the same direction. Consequently, breakage of parts will usually fol-.. low. The same situation arises ifa vibrator lever. and gear are; maintained in lowered positionifor two,successive revolutions. 1

It 's necessaryj therefore, that all inactive levers :be maintained in intermediate-or neutral. position. This is; accomplished with the regular or working levers by providing links. 40 ,of. ;intermediate height, by which the levers are held in the position shown in Fig. 1;" Whereextra levers are to be. maintained inoperative fo'ran indefinite periodfl provide an attachment which'avoids the necessity of building up a long and heavy chain of intermediate links for each such lever.

My improved attachment comprises a series of supporting members 50, provided with hub portions 51 and set screws 52. These members are conveniently mounted upon the rock shaft 54 which supports the usual lock bar 55 by which the vibrator levers 14 are held in high, low or intermediate position during the beating up of the weft.

The rock shaft is commonly moved angularly by a cam 56 which engages a cam fol.-

high, lou and intermediate positions, a looking bar for said levers movable to operative and inoperative positions, and means additional to said pattern means and to said locking bar effective to hold selected levers in intermediate position when said pattern means and said locking bar are both inoperative with respect to said levers.

In testimony whereof I have hereunto aflixed my signature. 1

' WILLIAM M. WATTIE.

lower 57 'on an arm 58 secured "on the rock 1 V shaft 54. A spring 59 (Fig. 1) causes the cam follower 57 to firmly engage the cam 56 and moves the rock shaft to theinoperative position shown in full lines in Fig. 2.

When it is desired to render a number of thelevers 14 inoperative, the rock shaft 54 is pulled partially out of the frame 12, so that a desired number of supporting members 50 maybe placed on the shaft. The parts are then re-asseinbled and the members 50 are secured to the rock shaft by the set screws 52 in such position that they will engage and support the selected vibrator levers 14, holding them in intermediate or neutral position. The slight rocking movement of the shaft 54 does not interfere with the effective support of the levers 14 by the members 50.

By the simple provision of the members 50 I avoid the necessity of building up a long and heavy pattern chain to maintain the extra levers in neutral position.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed,='other wise than as set forth in the claims, but what I claim is I 1. In a dobby head, a plurality of vibrator levers, pattern means to support said levers in high, low and intermediate positions, and additional devices by which selected levers may be supported in intermediate position, said devices being removably mounted in said dobby head 7 2. In a dobby head, a plurality of vibrator levers,"pattern means to support said levers inihigh, low and intermediate positions, a plurality of supporting members each effective to support a selected vibrator lever in intermediate position, and means to detach ably secure said members in operative position.

3. In a dobby head, a plurality of-vibrator levers, pattern means to support said lovers in high, low and intermediate positions, a lock bar, means including a rock shaft for positioning said bar, and a plurality of supporting members detachably secured to said rock shaft and positioned to support selected vibrator levers in intermediate position.

4. 'In a dobby head, a plurality of vibrator levers, pattern means to support said levers in 

